<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>   
</head>
<body>
    <h2>hello</h2>
    <!-- 行内嵌套(几乎不用) -->
    <div onclick="alert('行内嵌套')">js</div>
    <a href="javascript:alert('行内嵌套')">js</a>
    <p>hello world today is </p>
    <img src="img/bea.jpg" alt="" srcset="">

    <!-- 页面嵌套 -->
    <script>

        //DOM 修改页面内容
        document.write("hello dom")

        //BOM 控制浏览器的
        // alert("hello world")

        console.log("hello")
        console.log("hello text,js")
    </script>
    <!-- 外链 (最常用)-->
    <script src="./js/01_helloWorld.js">
        
    </script>
</body>
</html>